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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * processor_throttling.c - Throttling submodule of the ACPI processor driver
4 *
5 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de>
8 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
9 * - Added processor hotplug support
10 */
11
12#include <linux/kernel.h>
13#include <linux/module.h>
14#include <linux/slab.h>
15#include <linux/init.h>
16#include <linux/sched.h>
17#include <linux/cpufreq.h>
18#include <linux/acpi.h>
19#include <acpi/processor.h>
20#include <asm/io.h>
21#include <linux/uaccess.h>
22
23#define PREFIX "ACPI: "
24
25#define ACPI_PROCESSOR_CLASS "processor"
26#define _COMPONENT ACPI_PROCESSOR_COMPONENT
27ACPI_MODULE_NAME("processor_throttling");
28
29/* ignore_tpc:
30 * 0 -> acpi processor driver doesn't ignore _TPC values
31 * 1 -> acpi processor driver ignores _TPC values
32 */
33static int ignore_tpc;
34module_param(ignore_tpc, int, 0644);
35MODULE_PARM_DESC(ignore_tpc, "Disable broken BIOS _TPC throttling support");
36
37struct throttling_tstate {
38 unsigned int cpu; /* cpu nr */
39 int target_state; /* target T-state */
40};
41
42struct acpi_processor_throttling_arg {
43 struct acpi_processor *pr;
44 int target_state;
45 bool force;
46};
47
48#define THROTTLING_PRECHANGE (1)
49#define THROTTLING_POSTCHANGE (2)
50
51static int acpi_processor_get_throttling(struct acpi_processor *pr);
52static int __acpi_processor_set_throttling(struct acpi_processor *pr,
53 int state, bool force, bool direct);
54
55static int acpi_processor_update_tsd_coord(void)
56{
57 int count, count_target;
58 int retval = 0;
59 unsigned int i, j;
60 cpumask_var_t covered_cpus;
61 struct acpi_processor *pr, *match_pr;
62 struct acpi_tsd_package *pdomain, *match_pdomain;
63 struct acpi_processor_throttling *pthrottling, *match_pthrottling;
64
65 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))
66 return -ENOMEM;
67
68 /*
69 * Now that we have _TSD data from all CPUs, lets setup T-state
70 * coordination between all CPUs.
71 */
72 for_each_possible_cpu(i) {
73 pr = per_cpu(processors, i);
74 if (!pr)
75 continue;
76
77 /* Basic validity check for domain info */
78 pthrottling = &(pr->throttling);
79
80 /*
81 * If tsd package for one cpu is invalid, the coordination
82 * among all CPUs is thought as invalid.
83 * Maybe it is ugly.
84 */
85 if (!pthrottling->tsd_valid_flag) {
86 retval = -EINVAL;
87 break;
88 }
89 }
90 if (retval)
91 goto err_ret;
92
93 for_each_possible_cpu(i) {
94 pr = per_cpu(processors, i);
95 if (!pr)
96 continue;
97
98 if (cpumask_test_cpu(i, covered_cpus))
99 continue;
100 pthrottling = &pr->throttling;
101
102 pdomain = &(pthrottling->domain_info);
103 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
104 cpumask_set_cpu(i, covered_cpus);
105 /*
106 * If the number of processor in the TSD domain is 1, it is
107 * unnecessary to parse the coordination for this CPU.
108 */
109 if (pdomain->num_processors <= 1)
110 continue;
111
112 /* Validate the Domain info */
113 count_target = pdomain->num_processors;
114 count = 1;
115
116 for_each_possible_cpu(j) {
117 if (i == j)
118 continue;
119
120 match_pr = per_cpu(processors, j);
121 if (!match_pr)
122 continue;
123
124 match_pthrottling = &(match_pr->throttling);
125 match_pdomain = &(match_pthrottling->domain_info);
126 if (match_pdomain->domain != pdomain->domain)
127 continue;
128
129 /* Here i and j are in the same domain.
130 * If two TSD packages have the same domain, they
131 * should have the same num_porcessors and
132 * coordination type. Otherwise it will be regarded
133 * as illegal.
134 */
135 if (match_pdomain->num_processors != count_target) {
136 retval = -EINVAL;
137 goto err_ret;
138 }
139
140 if (pdomain->coord_type != match_pdomain->coord_type) {
141 retval = -EINVAL;
142 goto err_ret;
143 }
144
145 cpumask_set_cpu(j, covered_cpus);
146 cpumask_set_cpu(j, pthrottling->shared_cpu_map);
147 count++;
148 }
149 for_each_possible_cpu(j) {
150 if (i == j)
151 continue;
152
153 match_pr = per_cpu(processors, j);
154 if (!match_pr)
155 continue;
156
157 match_pthrottling = &(match_pr->throttling);
158 match_pdomain = &(match_pthrottling->domain_info);
159 if (match_pdomain->domain != pdomain->domain)
160 continue;
161
162 /*
163 * If some CPUS have the same domain, they
164 * will have the same shared_cpu_map.
165 */
166 cpumask_copy(match_pthrottling->shared_cpu_map,
167 pthrottling->shared_cpu_map);
168 }
169 }
170
171err_ret:
172 free_cpumask_var(covered_cpus);
173
174 for_each_possible_cpu(i) {
175 pr = per_cpu(processors, i);
176 if (!pr)
177 continue;
178
179 /*
180 * Assume no coordination on any error parsing domain info.
181 * The coordination type will be forced as SW_ALL.
182 */
183 if (retval) {
184 pthrottling = &(pr->throttling);
185 cpumask_clear(pthrottling->shared_cpu_map);
186 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
187 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
188 }
189 }
190
191 return retval;
192}
193
194/*
195 * Update the T-state coordination after the _TSD
196 * data for all cpus is obtained.
197 */
198void acpi_processor_throttling_init(void)
199{
200 if (acpi_processor_update_tsd_coord()) {
201 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
202 "Assume no T-state coordination\n"));
203 }
204
205 return;
206}
207
208static int acpi_processor_throttling_notifier(unsigned long event, void *data)
209{
210 struct throttling_tstate *p_tstate = data;
211 struct acpi_processor *pr;
212 unsigned int cpu ;
213 int target_state;
214 struct acpi_processor_limit *p_limit;
215 struct acpi_processor_throttling *p_throttling;
216
217 cpu = p_tstate->cpu;
218 pr = per_cpu(processors, cpu);
219 if (!pr) {
220 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid pr pointer\n"));
221 return 0;
222 }
223 if (!pr->flags.throttling) {
224 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling control is "
225 "unsupported on CPU %d\n", cpu));
226 return 0;
227 }
228 target_state = p_tstate->target_state;
229 p_throttling = &(pr->throttling);
230 switch (event) {
231 case THROTTLING_PRECHANGE:
232 /*
233 * Prechange event is used to choose one proper t-state,
234 * which meets the limits of thermal, user and _TPC.
235 */
236 p_limit = &pr->limit;
237 if (p_limit->thermal.tx > target_state)
238 target_state = p_limit->thermal.tx;
239 if (p_limit->user.tx > target_state)
240 target_state = p_limit->user.tx;
241 if (pr->throttling_platform_limit > target_state)
242 target_state = pr->throttling_platform_limit;
243 if (target_state >= p_throttling->state_count) {
244 printk(KERN_WARNING
245 "Exceed the limit of T-state \n");
246 target_state = p_throttling->state_count - 1;
247 }
248 p_tstate->target_state = target_state;
249 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PreChange Event:"
250 "target T-state of CPU %d is T%d\n",
251 cpu, target_state));
252 break;
253 case THROTTLING_POSTCHANGE:
254 /*
255 * Postchange event is only used to update the
256 * T-state flag of acpi_processor_throttling.
257 */
258 p_throttling->state = target_state;
259 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PostChange Event:"
260 "CPU %d is switched to T%d\n",
261 cpu, target_state));
262 break;
263 default:
264 printk(KERN_WARNING
265 "Unsupported Throttling notifier event\n");
266 break;
267 }
268
269 return 0;
270}
271
272/*
273 * _TPC - Throttling Present Capabilities
274 */
275static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
276{
277 acpi_status status = 0;
278 unsigned long long tpc = 0;
279
280 if (!pr)
281 return -EINVAL;
282
283 if (ignore_tpc)
284 goto end;
285
286 status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
287 if (ACPI_FAILURE(status)) {
288 if (status != AE_NOT_FOUND) {
289 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC"));
290 }
291 return -ENODEV;
292 }
293
294end:
295 pr->throttling_platform_limit = (int)tpc;
296 return 0;
297}
298
299int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
300{
301 int result = 0;
302 int throttling_limit;
303 int current_state;
304 struct acpi_processor_limit *limit;
305 int target_state;
306
307 if (ignore_tpc)
308 return 0;
309
310 result = acpi_processor_get_platform_limit(pr);
311 if (result) {
312 /* Throttling Limit is unsupported */
313 return result;
314 }
315
316 throttling_limit = pr->throttling_platform_limit;
317 if (throttling_limit >= pr->throttling.state_count) {
318 /* Uncorrect Throttling Limit */
319 return -EINVAL;
320 }
321
322 current_state = pr->throttling.state;
323 if (current_state > throttling_limit) {
324 /*
325 * The current state can meet the requirement of
326 * _TPC limit. But it is reasonable that OSPM changes
327 * t-states from high to low for better performance.
328 * Of course the limit condition of thermal
329 * and user should be considered.
330 */
331 limit = &pr->limit;
332 target_state = throttling_limit;
333 if (limit->thermal.tx > target_state)
334 target_state = limit->thermal.tx;
335 if (limit->user.tx > target_state)
336 target_state = limit->user.tx;
337 } else if (current_state == throttling_limit) {
338 /*
339 * Unnecessary to change the throttling state
340 */
341 return 0;
342 } else {
343 /*
344 * If the current state is lower than the limit of _TPC, it
345 * will be forced to switch to the throttling state defined
346 * by throttling_platfor_limit.
347 * Because the previous state meets with the limit condition
348 * of thermal and user, it is unnecessary to check it again.
349 */
350 target_state = throttling_limit;
351 }
352 return acpi_processor_set_throttling(pr, target_state, false);
353}
354
355/*
356 * This function is used to reevaluate whether the T-state is valid
357 * after one CPU is onlined/offlined.
358 * It is noted that it won't reevaluate the following properties for
359 * the T-state.
360 * 1. Control method.
361 * 2. the number of supported T-state
362 * 3. TSD domain
363 */
364void acpi_processor_reevaluate_tstate(struct acpi_processor *pr,
365 bool is_dead)
366{
367 int result = 0;
368
369 if (is_dead) {
370 /* When one CPU is offline, the T-state throttling
371 * will be invalidated.
372 */
373 pr->flags.throttling = 0;
374 return;
375 }
376 /* the following is to recheck whether the T-state is valid for
377 * the online CPU
378 */
379 if (!pr->throttling.state_count) {
380 /* If the number of T-state is invalid, it is
381 * invalidated.
382 */
383 pr->flags.throttling = 0;
384 return;
385 }
386 pr->flags.throttling = 1;
387
388 /* Disable throttling (if enabled). We'll let subsequent
389 * policy (e.g.thermal) decide to lower performance if it
390 * so chooses, but for now we'll crank up the speed.
391 */
392
393 result = acpi_processor_get_throttling(pr);
394 if (result)
395 goto end;
396
397 if (pr->throttling.state) {
398 result = acpi_processor_set_throttling(pr, 0, false);
399 if (result)
400 goto end;
401 }
402
403end:
404 if (result)
405 pr->flags.throttling = 0;
406}
407/*
408 * _PTC - Processor Throttling Control (and status) register location
409 */
410static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
411{
412 int result = 0;
413 acpi_status status = 0;
414 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
415 union acpi_object *ptc = NULL;
416 union acpi_object obj = { 0 };
417 struct acpi_processor_throttling *throttling;
418
419 status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
420 if (ACPI_FAILURE(status)) {
421 if (status != AE_NOT_FOUND) {
422 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
423 }
424 return -ENODEV;
425 }
426
427 ptc = (union acpi_object *)buffer.pointer;
428 if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE)
429 || (ptc->package.count != 2)) {
430 printk(KERN_ERR PREFIX "Invalid _PTC data\n");
431 result = -EFAULT;
432 goto end;
433 }
434
435 /*
436 * control_register
437 */
438
439 obj = ptc->package.elements[0];
440
441 if ((obj.type != ACPI_TYPE_BUFFER)
442 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
443 || (obj.buffer.pointer == NULL)) {
444 printk(KERN_ERR PREFIX
445 "Invalid _PTC data (control_register)\n");
446 result = -EFAULT;
447 goto end;
448 }
449 memcpy(&pr->throttling.control_register, obj.buffer.pointer,
450 sizeof(struct acpi_ptc_register));
451
452 /*
453 * status_register
454 */
455
456 obj = ptc->package.elements[1];
457
458 if ((obj.type != ACPI_TYPE_BUFFER)
459 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
460 || (obj.buffer.pointer == NULL)) {
461 printk(KERN_ERR PREFIX "Invalid _PTC data (status_register)\n");
462 result = -EFAULT;
463 goto end;
464 }
465
466 memcpy(&pr->throttling.status_register, obj.buffer.pointer,
467 sizeof(struct acpi_ptc_register));
468
469 throttling = &pr->throttling;
470
471 if ((throttling->control_register.bit_width +
472 throttling->control_register.bit_offset) > 32) {
473 printk(KERN_ERR PREFIX "Invalid _PTC control register\n");
474 result = -EFAULT;
475 goto end;
476 }
477
478 if ((throttling->status_register.bit_width +
479 throttling->status_register.bit_offset) > 32) {
480 printk(KERN_ERR PREFIX "Invalid _PTC status register\n");
481 result = -EFAULT;
482 goto end;
483 }
484
485 end:
486 kfree(buffer.pointer);
487
488 return result;
489}
490
491/*
492 * _TSS - Throttling Supported States
493 */
494static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
495{
496 int result = 0;
497 acpi_status status = AE_OK;
498 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
499 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
500 struct acpi_buffer state = { 0, NULL };
501 union acpi_object *tss = NULL;
502 int i;
503
504 status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
505 if (ACPI_FAILURE(status)) {
506 if (status != AE_NOT_FOUND) {
507 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
508 }
509 return -ENODEV;
510 }
511
512 tss = buffer.pointer;
513 if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) {
514 printk(KERN_ERR PREFIX "Invalid _TSS data\n");
515 result = -EFAULT;
516 goto end;
517 }
518
519 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
520 tss->package.count));
521
522 pr->throttling.state_count = tss->package.count;
523 pr->throttling.states_tss =
524 kmalloc_array(tss->package.count,
525 sizeof(struct acpi_processor_tx_tss),
526 GFP_KERNEL);
527 if (!pr->throttling.states_tss) {
528 result = -ENOMEM;
529 goto end;
530 }
531
532 for (i = 0; i < pr->throttling.state_count; i++) {
533
534 struct acpi_processor_tx_tss *tx =
535 (struct acpi_processor_tx_tss *)&(pr->throttling.
536 states_tss[i]);
537
538 state.length = sizeof(struct acpi_processor_tx_tss);
539 state.pointer = tx;
540
541 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
542
543 status = acpi_extract_package(&(tss->package.elements[i]),
544 &format, &state);
545 if (ACPI_FAILURE(status)) {
546 ACPI_EXCEPTION((AE_INFO, status, "Invalid _TSS data"));
547 result = -EFAULT;
548 kfree(pr->throttling.states_tss);
549 goto end;
550 }
551
552 if (!tx->freqpercentage) {
553 printk(KERN_ERR PREFIX
554 "Invalid _TSS data: freq is zero\n");
555 result = -EFAULT;
556 kfree(pr->throttling.states_tss);
557 goto end;
558 }
559 }
560
561 end:
562 kfree(buffer.pointer);
563
564 return result;
565}
566
567/*
568 * _TSD - T-State Dependencies
569 */
570static int acpi_processor_get_tsd(struct acpi_processor *pr)
571{
572 int result = 0;
573 acpi_status status = AE_OK;
574 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
575 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
576 struct acpi_buffer state = { 0, NULL };
577 union acpi_object *tsd = NULL;
578 struct acpi_tsd_package *pdomain;
579 struct acpi_processor_throttling *pthrottling;
580
581 pthrottling = &pr->throttling;
582 pthrottling->tsd_valid_flag = 0;
583
584 status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
585 if (ACPI_FAILURE(status)) {
586 if (status != AE_NOT_FOUND) {
587 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD"));
588 }
589 return -ENODEV;
590 }
591
592 tsd = buffer.pointer;
593 if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) {
594 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
595 result = -EFAULT;
596 goto end;
597 }
598
599 if (tsd->package.count != 1) {
600 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
601 result = -EFAULT;
602 goto end;
603 }
604
605 pdomain = &(pr->throttling.domain_info);
606
607 state.length = sizeof(struct acpi_tsd_package);
608 state.pointer = pdomain;
609
610 status = acpi_extract_package(&(tsd->package.elements[0]),
611 &format, &state);
612 if (ACPI_FAILURE(status)) {
613 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
614 result = -EFAULT;
615 goto end;
616 }
617
618 if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) {
619 printk(KERN_ERR PREFIX "Unknown _TSD:num_entries\n");
620 result = -EFAULT;
621 goto end;
622 }
623
624 if (pdomain->revision != ACPI_TSD_REV0_REVISION) {
625 printk(KERN_ERR PREFIX "Unknown _TSD:revision\n");
626 result = -EFAULT;
627 goto end;
628 }
629
630 pthrottling = &pr->throttling;
631 pthrottling->tsd_valid_flag = 1;
632 pthrottling->shared_type = pdomain->coord_type;
633 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
634 /*
635 * If the coordination type is not defined in ACPI spec,
636 * the tsd_valid_flag will be clear and coordination type
637 * will be forecd as DOMAIN_COORD_TYPE_SW_ALL.
638 */
639 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
640 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
641 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
642 pthrottling->tsd_valid_flag = 0;
643 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
644 }
645
646 end:
647 kfree(buffer.pointer);
648 return result;
649}
650
651/* --------------------------------------------------------------------------
652 Throttling Control
653 -------------------------------------------------------------------------- */
654static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr)
655{
656 int state = 0;
657 u32 value = 0;
658 u32 duty_mask = 0;
659 u32 duty_value = 0;
660
661 if (!pr)
662 return -EINVAL;
663
664 if (!pr->flags.throttling)
665 return -ENODEV;
666
667 /*
668 * We don't care about error returns - we just try to mark
669 * these reserved so that nobody else is confused into thinking
670 * that this region might be unused..
671 *
672 * (In particular, allocating the IO range for Cardbus)
673 */
674 request_region(pr->throttling.address, 6, "ACPI CPU throttle");
675
676 pr->throttling.state = 0;
677
678 duty_mask = pr->throttling.state_count - 1;
679
680 duty_mask <<= pr->throttling.duty_offset;
681
682 local_irq_disable();
683
684 value = inl(pr->throttling.address);
685
686 /*
687 * Compute the current throttling state when throttling is enabled
688 * (bit 4 is on).
689 */
690 if (value & 0x10) {
691 duty_value = value & duty_mask;
692 duty_value >>= pr->throttling.duty_offset;
693
694 if (duty_value)
695 state = pr->throttling.state_count - duty_value;
696 }
697
698 pr->throttling.state = state;
699
700 local_irq_enable();
701
702 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
703 "Throttling state is T%d (%d%% throttling applied)\n",
704 state, pr->throttling.states[state].performance));
705
706 return 0;
707}
708
709#ifdef CONFIG_X86
710static int acpi_throttling_rdmsr(u64 *value)
711{
712 u64 msr_high, msr_low;
713 u64 msr = 0;
714 int ret = -1;
715
716 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
717 !this_cpu_has(X86_FEATURE_ACPI)) {
718 printk(KERN_ERR PREFIX
719 "HARDWARE addr space,NOT supported yet\n");
720 } else {
721 msr_low = 0;
722 msr_high = 0;
723 rdmsr_safe(MSR_IA32_THERM_CONTROL,
724 (u32 *)&msr_low , (u32 *) &msr_high);
725 msr = (msr_high << 32) | msr_low;
726 *value = (u64) msr;
727 ret = 0;
728 }
729 return ret;
730}
731
732static int acpi_throttling_wrmsr(u64 value)
733{
734 int ret = -1;
735 u64 msr;
736
737 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
738 !this_cpu_has(X86_FEATURE_ACPI)) {
739 printk(KERN_ERR PREFIX
740 "HARDWARE addr space,NOT supported yet\n");
741 } else {
742 msr = value;
743 wrmsr_safe(MSR_IA32_THERM_CONTROL,
744 msr & 0xffffffff, msr >> 32);
745 ret = 0;
746 }
747 return ret;
748}
749#else
750static int acpi_throttling_rdmsr(u64 *value)
751{
752 printk(KERN_ERR PREFIX
753 "HARDWARE addr space,NOT supported yet\n");
754 return -1;
755}
756
757static int acpi_throttling_wrmsr(u64 value)
758{
759 printk(KERN_ERR PREFIX
760 "HARDWARE addr space,NOT supported yet\n");
761 return -1;
762}
763#endif
764
765static int acpi_read_throttling_status(struct acpi_processor *pr,
766 u64 *value)
767{
768 u32 bit_width, bit_offset;
769 u32 ptc_value;
770 u64 ptc_mask;
771 struct acpi_processor_throttling *throttling;
772 int ret = -1;
773
774 throttling = &pr->throttling;
775 switch (throttling->status_register.space_id) {
776 case ACPI_ADR_SPACE_SYSTEM_IO:
777 bit_width = throttling->status_register.bit_width;
778 bit_offset = throttling->status_register.bit_offset;
779
780 acpi_os_read_port((acpi_io_address) throttling->status_register.
781 address, &ptc_value,
782 (u32) (bit_width + bit_offset));
783 ptc_mask = (1 << bit_width) - 1;
784 *value = (u64) ((ptc_value >> bit_offset) & ptc_mask);
785 ret = 0;
786 break;
787 case ACPI_ADR_SPACE_FIXED_HARDWARE:
788 ret = acpi_throttling_rdmsr(value);
789 break;
790 default:
791 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
792 (u32) (throttling->status_register.space_id));
793 }
794 return ret;
795}
796
797static int acpi_write_throttling_state(struct acpi_processor *pr,
798 u64 value)
799{
800 u32 bit_width, bit_offset;
801 u64 ptc_value;
802 u64 ptc_mask;
803 struct acpi_processor_throttling *throttling;
804 int ret = -1;
805
806 throttling = &pr->throttling;
807 switch (throttling->control_register.space_id) {
808 case ACPI_ADR_SPACE_SYSTEM_IO:
809 bit_width = throttling->control_register.bit_width;
810 bit_offset = throttling->control_register.bit_offset;
811 ptc_mask = (1 << bit_width) - 1;
812 ptc_value = value & ptc_mask;
813
814 acpi_os_write_port((acpi_io_address) throttling->
815 control_register.address,
816 (u32) (ptc_value << bit_offset),
817 (u32) (bit_width + bit_offset));
818 ret = 0;
819 break;
820 case ACPI_ADR_SPACE_FIXED_HARDWARE:
821 ret = acpi_throttling_wrmsr(value);
822 break;
823 default:
824 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
825 (u32) (throttling->control_register.space_id));
826 }
827 return ret;
828}
829
830static int acpi_get_throttling_state(struct acpi_processor *pr,
831 u64 value)
832{
833 int i;
834
835 for (i = 0; i < pr->throttling.state_count; i++) {
836 struct acpi_processor_tx_tss *tx =
837 (struct acpi_processor_tx_tss *)&(pr->throttling.
838 states_tss[i]);
839 if (tx->control == value)
840 return i;
841 }
842 return -1;
843}
844
845static int acpi_get_throttling_value(struct acpi_processor *pr,
846 int state, u64 *value)
847{
848 int ret = -1;
849
850 if (state >= 0 && state <= pr->throttling.state_count) {
851 struct acpi_processor_tx_tss *tx =
852 (struct acpi_processor_tx_tss *)&(pr->throttling.
853 states_tss[state]);
854 *value = tx->control;
855 ret = 0;
856 }
857 return ret;
858}
859
860static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
861{
862 int state = 0;
863 int ret;
864 u64 value;
865
866 if (!pr)
867 return -EINVAL;
868
869 if (!pr->flags.throttling)
870 return -ENODEV;
871
872 pr->throttling.state = 0;
873
874 value = 0;
875 ret = acpi_read_throttling_status(pr, &value);
876 if (ret >= 0) {
877 state = acpi_get_throttling_state(pr, value);
878 if (state == -1) {
879 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
880 "Invalid throttling state, reset\n"));
881 state = 0;
882 ret = __acpi_processor_set_throttling(pr, state, true,
883 true);
884 if (ret)
885 return ret;
886 }
887 pr->throttling.state = state;
888 }
889
890 return 0;
891}
892
893static long __acpi_processor_get_throttling(void *data)
894{
895 struct acpi_processor *pr = data;
896
897 return pr->throttling.acpi_processor_get_throttling(pr);
898}
899
900static int acpi_processor_get_throttling(struct acpi_processor *pr)
901{
902 if (!pr)
903 return -EINVAL;
904
905 if (!pr->flags.throttling)
906 return -ENODEV;
907
908 /*
909 * This is either called from the CPU hotplug callback of
910 * processor_driver or via the ACPI probe function. In the latter
911 * case the CPU is not guaranteed to be online. Both call sites are
912 * protected against CPU hotplug.
913 */
914 if (!cpu_online(pr->id))
915 return -ENODEV;
916
917 return call_on_cpu(pr->id, __acpi_processor_get_throttling, pr, false);
918}
919
920static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
921{
922 int i, step;
923
924 if (!pr->throttling.address) {
925 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
926 return -EINVAL;
927 } else if (!pr->throttling.duty_width) {
928 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
929 return -EINVAL;
930 }
931 /* TBD: Support duty_cycle values that span bit 4. */
932 else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
933 printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
934 return -EINVAL;
935 }
936
937 pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
938
939 /*
940 * Compute state values. Note that throttling displays a linear power
941 * performance relationship (at 50% performance the CPU will consume
942 * 50% power). Values are in 1/10th of a percent to preserve accuracy.
943 */
944
945 step = (1000 / pr->throttling.state_count);
946
947 for (i = 0; i < pr->throttling.state_count; i++) {
948 pr->throttling.states[i].performance = 1000 - step * i;
949 pr->throttling.states[i].power = 1000 - step * i;
950 }
951 return 0;
952}
953
954static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
955 int state, bool force)
956{
957 u32 value = 0;
958 u32 duty_mask = 0;
959 u32 duty_value = 0;
960
961 if (!pr)
962 return -EINVAL;
963
964 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
965 return -EINVAL;
966
967 if (!pr->flags.throttling)
968 return -ENODEV;
969
970 if (!force && (state == pr->throttling.state))
971 return 0;
972
973 if (state < pr->throttling_platform_limit)
974 return -EPERM;
975 /*
976 * Calculate the duty_value and duty_mask.
977 */
978 if (state) {
979 duty_value = pr->throttling.state_count - state;
980
981 duty_value <<= pr->throttling.duty_offset;
982
983 /* Used to clear all duty_value bits */
984 duty_mask = pr->throttling.state_count - 1;
985
986 duty_mask <<= acpi_gbl_FADT.duty_offset;
987 duty_mask = ~duty_mask;
988 }
989
990 local_irq_disable();
991
992 /*
993 * Disable throttling by writing a 0 to bit 4. Note that we must
994 * turn it off before you can change the duty_value.
995 */
996 value = inl(pr->throttling.address);
997 if (value & 0x10) {
998 value &= 0xFFFFFFEF;
999 outl(value, pr->throttling.address);
1000 }
1001
1002 /*
1003 * Write the new duty_value and then enable throttling. Note
1004 * that a state value of 0 leaves throttling disabled.
1005 */
1006 if (state) {
1007 value &= duty_mask;
1008 value |= duty_value;
1009 outl(value, pr->throttling.address);
1010
1011 value |= 0x00000010;
1012 outl(value, pr->throttling.address);
1013 }
1014
1015 pr->throttling.state = state;
1016
1017 local_irq_enable();
1018
1019 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1020 "Throttling state set to T%d (%d%%)\n", state,
1021 (pr->throttling.states[state].performance ? pr->
1022 throttling.states[state].performance / 10 : 0)));
1023
1024 return 0;
1025}
1026
1027static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
1028 int state, bool force)
1029{
1030 int ret;
1031 u64 value;
1032
1033 if (!pr)
1034 return -EINVAL;
1035
1036 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1037 return -EINVAL;
1038
1039 if (!pr->flags.throttling)
1040 return -ENODEV;
1041
1042 if (!force && (state == pr->throttling.state))
1043 return 0;
1044
1045 if (state < pr->throttling_platform_limit)
1046 return -EPERM;
1047
1048 value = 0;
1049 ret = acpi_get_throttling_value(pr, state, &value);
1050 if (ret >= 0) {
1051 acpi_write_throttling_state(pr, value);
1052 pr->throttling.state = state;
1053 }
1054
1055 return 0;
1056}
1057
1058static long acpi_processor_throttling_fn(void *data)
1059{
1060 struct acpi_processor_throttling_arg *arg = data;
1061 struct acpi_processor *pr = arg->pr;
1062
1063 return pr->throttling.acpi_processor_set_throttling(pr,
1064 arg->target_state, arg->force);
1065}
1066
1067static int __acpi_processor_set_throttling(struct acpi_processor *pr,
1068 int state, bool force, bool direct)
1069{
1070 int ret = 0;
1071 unsigned int i;
1072 struct acpi_processor *match_pr;
1073 struct acpi_processor_throttling *p_throttling;
1074 struct acpi_processor_throttling_arg arg;
1075 struct throttling_tstate t_state;
1076
1077 if (!pr)
1078 return -EINVAL;
1079
1080 if (!pr->flags.throttling)
1081 return -ENODEV;
1082
1083 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1084 return -EINVAL;
1085
1086 if (cpu_is_offline(pr->id)) {
1087 /*
1088 * the cpu pointed by pr->id is offline. Unnecessary to change
1089 * the throttling state any more.
1090 */
1091 return -ENODEV;
1092 }
1093
1094 t_state.target_state = state;
1095 p_throttling = &(pr->throttling);
1096
1097 /*
1098 * The throttling notifier will be called for every
1099 * affected cpu in order to get one proper T-state.
1100 * The notifier event is THROTTLING_PRECHANGE.
1101 */
1102 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
1103 t_state.cpu = i;
1104 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
1105 &t_state);
1106 }
1107 /*
1108 * The function of acpi_processor_set_throttling will be called
1109 * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1110 * it is necessary to call it for every affected cpu. Otherwise
1111 * it can be called only for the cpu pointed by pr.
1112 */
1113 if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
1114 arg.pr = pr;
1115 arg.target_state = state;
1116 arg.force = force;
1117 ret = call_on_cpu(pr->id, acpi_processor_throttling_fn, &arg,
1118 direct);
1119 } else {
1120 /*
1121 * When the T-state coordination is SW_ALL or HW_ALL,
1122 * it is necessary to set T-state for every affected
1123 * cpus.
1124 */
1125 for_each_cpu_and(i, cpu_online_mask,
1126 p_throttling->shared_cpu_map) {
1127 match_pr = per_cpu(processors, i);
1128 /*
1129 * If the pointer is invalid, we will report the
1130 * error message and continue.
1131 */
1132 if (!match_pr) {
1133 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1134 "Invalid Pointer for CPU %d\n", i));
1135 continue;
1136 }
1137 /*
1138 * If the throttling control is unsupported on CPU i,
1139 * we will report the error message and continue.
1140 */
1141 if (!match_pr->flags.throttling) {
1142 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1143 "Throttling Control is unsupported "
1144 "on CPU %d\n", i));
1145 continue;
1146 }
1147
1148 arg.pr = match_pr;
1149 arg.target_state = state;
1150 arg.force = force;
1151 ret = call_on_cpu(pr->id, acpi_processor_throttling_fn,
1152 &arg, direct);
1153 }
1154 }
1155 /*
1156 * After the set_throttling is called, the
1157 * throttling notifier is called for every
1158 * affected cpu to update the T-states.
1159 * The notifier event is THROTTLING_POSTCHANGE
1160 */
1161 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
1162 t_state.cpu = i;
1163 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1164 &t_state);
1165 }
1166
1167 return ret;
1168}
1169
1170int acpi_processor_set_throttling(struct acpi_processor *pr, int state,
1171 bool force)
1172{
1173 return __acpi_processor_set_throttling(pr, state, force, false);
1174}
1175
1176int acpi_processor_get_throttling_info(struct acpi_processor *pr)
1177{
1178 int result = 0;
1179 struct acpi_processor_throttling *pthrottling;
1180
1181 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1182 "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1183 pr->throttling.address,
1184 pr->throttling.duty_offset,
1185 pr->throttling.duty_width));
1186
1187 /*
1188 * Evaluate _PTC, _TSS and _TPC
1189 * They must all be present or none of them can be used.
1190 */
1191 if (acpi_processor_get_throttling_control(pr) ||
1192 acpi_processor_get_throttling_states(pr) ||
1193 acpi_processor_get_platform_limit(pr))
1194 {
1195 pr->throttling.acpi_processor_get_throttling =
1196 &acpi_processor_get_throttling_fadt;
1197 pr->throttling.acpi_processor_set_throttling =
1198 &acpi_processor_set_throttling_fadt;
1199 if (acpi_processor_get_fadt_info(pr))
1200 return 0;
1201 } else {
1202 pr->throttling.acpi_processor_get_throttling =
1203 &acpi_processor_get_throttling_ptc;
1204 pr->throttling.acpi_processor_set_throttling =
1205 &acpi_processor_set_throttling_ptc;
1206 }
1207
1208 /*
1209 * If TSD package for one CPU can't be parsed successfully, it means
1210 * that this CPU will have no coordination with other CPUs.
1211 */
1212 if (acpi_processor_get_tsd(pr)) {
1213 pthrottling = &pr->throttling;
1214 pthrottling->tsd_valid_flag = 0;
1215 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
1216 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
1217 }
1218
1219 /*
1220 * PIIX4 Errata: We don't support throttling on the original PIIX4.
1221 * This shouldn't be an issue as few (if any) mobile systems ever
1222 * used this part.
1223 */
1224 if (errata.piix4.throttle) {
1225 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1226 "Throttling not supported on PIIX4 A- or B-step\n"));
1227 return 0;
1228 }
1229
1230 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
1231 pr->throttling.state_count));
1232
1233 pr->flags.throttling = 1;
1234
1235 /*
1236 * Disable throttling (if enabled). We'll let subsequent policy (e.g.
1237 * thermal) decide to lower performance if it so chooses, but for now
1238 * we'll crank up the speed.
1239 */
1240
1241 result = acpi_processor_get_throttling(pr);
1242 if (result)
1243 goto end;
1244
1245 if (pr->throttling.state) {
1246 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1247 "Disabling throttling (was T%d)\n",
1248 pr->throttling.state));
1249 result = acpi_processor_set_throttling(pr, 0, false);
1250 if (result)
1251 goto end;
1252 }
1253
1254 end:
1255 if (result)
1256 pr->flags.throttling = 0;
1257
1258 return result;
1259}
1260
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * processor_throttling.c - Throttling submodule of the ACPI processor driver
4 *
5 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de>
8 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
9 * - Added processor hotplug support
10 */
11
12#define pr_fmt(fmt) "ACPI: " fmt
13
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/slab.h>
17#include <linux/init.h>
18#include <linux/sched.h>
19#include <linux/cpufreq.h>
20#include <linux/acpi.h>
21#include <acpi/processor.h>
22#include <asm/io.h>
23#include <linux/uaccess.h>
24
25/* ignore_tpc:
26 * 0 -> acpi processor driver doesn't ignore _TPC values
27 * 1 -> acpi processor driver ignores _TPC values
28 */
29static int ignore_tpc;
30module_param(ignore_tpc, int, 0644);
31MODULE_PARM_DESC(ignore_tpc, "Disable broken BIOS _TPC throttling support");
32
33struct throttling_tstate {
34 unsigned int cpu; /* cpu nr */
35 int target_state; /* target T-state */
36};
37
38struct acpi_processor_throttling_arg {
39 struct acpi_processor *pr;
40 int target_state;
41 bool force;
42};
43
44#define THROTTLING_PRECHANGE (1)
45#define THROTTLING_POSTCHANGE (2)
46
47static int acpi_processor_get_throttling(struct acpi_processor *pr);
48static int __acpi_processor_set_throttling(struct acpi_processor *pr,
49 int state, bool force, bool direct);
50
51static int acpi_processor_update_tsd_coord(void)
52{
53 int count, count_target;
54 int retval = 0;
55 unsigned int i, j;
56 cpumask_var_t covered_cpus;
57 struct acpi_processor *pr, *match_pr;
58 struct acpi_tsd_package *pdomain, *match_pdomain;
59 struct acpi_processor_throttling *pthrottling, *match_pthrottling;
60
61 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))
62 return -ENOMEM;
63
64 /*
65 * Now that we have _TSD data from all CPUs, lets setup T-state
66 * coordination between all CPUs.
67 */
68 for_each_possible_cpu(i) {
69 pr = per_cpu(processors, i);
70 if (!pr)
71 continue;
72
73 /* Basic validity check for domain info */
74 pthrottling = &(pr->throttling);
75
76 /*
77 * If tsd package for one cpu is invalid, the coordination
78 * among all CPUs is thought as invalid.
79 * Maybe it is ugly.
80 */
81 if (!pthrottling->tsd_valid_flag) {
82 retval = -EINVAL;
83 break;
84 }
85 }
86 if (retval)
87 goto err_ret;
88
89 for_each_possible_cpu(i) {
90 pr = per_cpu(processors, i);
91 if (!pr)
92 continue;
93
94 if (cpumask_test_cpu(i, covered_cpus))
95 continue;
96 pthrottling = &pr->throttling;
97
98 pdomain = &(pthrottling->domain_info);
99 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
100 cpumask_set_cpu(i, covered_cpus);
101 /*
102 * If the number of processor in the TSD domain is 1, it is
103 * unnecessary to parse the coordination for this CPU.
104 */
105 if (pdomain->num_processors <= 1)
106 continue;
107
108 /* Validate the Domain info */
109 count_target = pdomain->num_processors;
110 count = 1;
111
112 for_each_possible_cpu(j) {
113 if (i == j)
114 continue;
115
116 match_pr = per_cpu(processors, j);
117 if (!match_pr)
118 continue;
119
120 match_pthrottling = &(match_pr->throttling);
121 match_pdomain = &(match_pthrottling->domain_info);
122 if (match_pdomain->domain != pdomain->domain)
123 continue;
124
125 /* Here i and j are in the same domain.
126 * If two TSD packages have the same domain, they
127 * should have the same num_porcessors and
128 * coordination type. Otherwise it will be regarded
129 * as illegal.
130 */
131 if (match_pdomain->num_processors != count_target) {
132 retval = -EINVAL;
133 goto err_ret;
134 }
135
136 if (pdomain->coord_type != match_pdomain->coord_type) {
137 retval = -EINVAL;
138 goto err_ret;
139 }
140
141 cpumask_set_cpu(j, covered_cpus);
142 cpumask_set_cpu(j, pthrottling->shared_cpu_map);
143 count++;
144 }
145 for_each_possible_cpu(j) {
146 if (i == j)
147 continue;
148
149 match_pr = per_cpu(processors, j);
150 if (!match_pr)
151 continue;
152
153 match_pthrottling = &(match_pr->throttling);
154 match_pdomain = &(match_pthrottling->domain_info);
155 if (match_pdomain->domain != pdomain->domain)
156 continue;
157
158 /*
159 * If some CPUS have the same domain, they
160 * will have the same shared_cpu_map.
161 */
162 cpumask_copy(match_pthrottling->shared_cpu_map,
163 pthrottling->shared_cpu_map);
164 }
165 }
166
167err_ret:
168 free_cpumask_var(covered_cpus);
169
170 for_each_possible_cpu(i) {
171 pr = per_cpu(processors, i);
172 if (!pr)
173 continue;
174
175 /*
176 * Assume no coordination on any error parsing domain info.
177 * The coordination type will be forced as SW_ALL.
178 */
179 if (retval) {
180 pthrottling = &(pr->throttling);
181 cpumask_clear(pthrottling->shared_cpu_map);
182 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
183 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
184 }
185 }
186
187 return retval;
188}
189
190/*
191 * Update the T-state coordination after the _TSD
192 * data for all cpus is obtained.
193 */
194void acpi_processor_throttling_init(void)
195{
196 if (acpi_processor_update_tsd_coord())
197 pr_debug("Assume no T-state coordination\n");
198}
199
200static int acpi_processor_throttling_notifier(unsigned long event, void *data)
201{
202 struct throttling_tstate *p_tstate = data;
203 struct acpi_processor *pr;
204 unsigned int cpu;
205 int target_state;
206 struct acpi_processor_limit *p_limit;
207 struct acpi_processor_throttling *p_throttling;
208
209 cpu = p_tstate->cpu;
210 pr = per_cpu(processors, cpu);
211 if (!pr) {
212 pr_debug("Invalid pr pointer\n");
213 return 0;
214 }
215 if (!pr->flags.throttling) {
216 acpi_handle_debug(pr->handle,
217 "Throttling control unsupported on CPU %d\n",
218 cpu);
219 return 0;
220 }
221 target_state = p_tstate->target_state;
222 p_throttling = &(pr->throttling);
223 switch (event) {
224 case THROTTLING_PRECHANGE:
225 /*
226 * Prechange event is used to choose one proper t-state,
227 * which meets the limits of thermal, user and _TPC.
228 */
229 p_limit = &pr->limit;
230 if (p_limit->thermal.tx > target_state)
231 target_state = p_limit->thermal.tx;
232 if (p_limit->user.tx > target_state)
233 target_state = p_limit->user.tx;
234 if (pr->throttling_platform_limit > target_state)
235 target_state = pr->throttling_platform_limit;
236 if (target_state >= p_throttling->state_count) {
237 pr_warn("Exceed the limit of T-state \n");
238 target_state = p_throttling->state_count - 1;
239 }
240 p_tstate->target_state = target_state;
241 acpi_handle_debug(pr->handle,
242 "PreChange Event: target T-state of CPU %d is T%d\n",
243 cpu, target_state);
244 break;
245 case THROTTLING_POSTCHANGE:
246 /*
247 * Postchange event is only used to update the
248 * T-state flag of acpi_processor_throttling.
249 */
250 p_throttling->state = target_state;
251 acpi_handle_debug(pr->handle,
252 "PostChange Event: CPU %d is switched to T%d\n",
253 cpu, target_state);
254 break;
255 default:
256 pr_warn("Unsupported Throttling notifier event\n");
257 break;
258 }
259
260 return 0;
261}
262
263/*
264 * _TPC - Throttling Present Capabilities
265 */
266static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
267{
268 acpi_status status = 0;
269 unsigned long long tpc = 0;
270
271 if (!pr)
272 return -EINVAL;
273
274 if (ignore_tpc)
275 goto end;
276
277 status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
278 if (ACPI_FAILURE(status)) {
279 if (status != AE_NOT_FOUND)
280 acpi_evaluation_failure_warn(pr->handle, "_TPC", status);
281
282 return -ENODEV;
283 }
284
285end:
286 pr->throttling_platform_limit = (int)tpc;
287 return 0;
288}
289
290int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
291{
292 int result = 0;
293 int throttling_limit;
294 int current_state;
295 struct acpi_processor_limit *limit;
296 int target_state;
297
298 if (ignore_tpc)
299 return 0;
300
301 result = acpi_processor_get_platform_limit(pr);
302 if (result) {
303 /* Throttling Limit is unsupported */
304 return result;
305 }
306
307 throttling_limit = pr->throttling_platform_limit;
308 if (throttling_limit >= pr->throttling.state_count) {
309 /* Uncorrect Throttling Limit */
310 return -EINVAL;
311 }
312
313 current_state = pr->throttling.state;
314 if (current_state > throttling_limit) {
315 /*
316 * The current state can meet the requirement of
317 * _TPC limit. But it is reasonable that OSPM changes
318 * t-states from high to low for better performance.
319 * Of course the limit condition of thermal
320 * and user should be considered.
321 */
322 limit = &pr->limit;
323 target_state = throttling_limit;
324 if (limit->thermal.tx > target_state)
325 target_state = limit->thermal.tx;
326 if (limit->user.tx > target_state)
327 target_state = limit->user.tx;
328 } else if (current_state == throttling_limit) {
329 /*
330 * Unnecessary to change the throttling state
331 */
332 return 0;
333 } else {
334 /*
335 * If the current state is lower than the limit of _TPC, it
336 * will be forced to switch to the throttling state defined
337 * by throttling_platfor_limit.
338 * Because the previous state meets with the limit condition
339 * of thermal and user, it is unnecessary to check it again.
340 */
341 target_state = throttling_limit;
342 }
343 return acpi_processor_set_throttling(pr, target_state, false);
344}
345
346/*
347 * This function is used to reevaluate whether the T-state is valid
348 * after one CPU is onlined/offlined.
349 * It is noted that it won't reevaluate the following properties for
350 * the T-state.
351 * 1. Control method.
352 * 2. the number of supported T-state
353 * 3. TSD domain
354 */
355void acpi_processor_reevaluate_tstate(struct acpi_processor *pr,
356 bool is_dead)
357{
358 int result = 0;
359
360 if (is_dead) {
361 /* When one CPU is offline, the T-state throttling
362 * will be invalidated.
363 */
364 pr->flags.throttling = 0;
365 return;
366 }
367 /* the following is to recheck whether the T-state is valid for
368 * the online CPU
369 */
370 if (!pr->throttling.state_count) {
371 /* If the number of T-state is invalid, it is
372 * invalidated.
373 */
374 pr->flags.throttling = 0;
375 return;
376 }
377 pr->flags.throttling = 1;
378
379 /* Disable throttling (if enabled). We'll let subsequent
380 * policy (e.g.thermal) decide to lower performance if it
381 * so chooses, but for now we'll crank up the speed.
382 */
383
384 result = acpi_processor_get_throttling(pr);
385 if (result)
386 goto end;
387
388 if (pr->throttling.state) {
389 result = acpi_processor_set_throttling(pr, 0, false);
390 if (result)
391 goto end;
392 }
393
394end:
395 if (result)
396 pr->flags.throttling = 0;
397}
398/*
399 * _PTC - Processor Throttling Control (and status) register location
400 */
401static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
402{
403 int result = 0;
404 acpi_status status = 0;
405 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
406 union acpi_object *ptc = NULL;
407 union acpi_object obj;
408 struct acpi_processor_throttling *throttling;
409
410 status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
411 if (ACPI_FAILURE(status)) {
412 if (status != AE_NOT_FOUND)
413 acpi_evaluation_failure_warn(pr->handle, "_PTC", status);
414
415 return -ENODEV;
416 }
417
418 ptc = (union acpi_object *)buffer.pointer;
419 if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE)
420 || (ptc->package.count != 2)) {
421 pr_err("Invalid _PTC data\n");
422 result = -EFAULT;
423 goto end;
424 }
425
426 /*
427 * control_register
428 */
429
430 obj = ptc->package.elements[0];
431
432 if ((obj.type != ACPI_TYPE_BUFFER)
433 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
434 || (obj.buffer.pointer == NULL)) {
435 pr_err("Invalid _PTC data (control_register)\n");
436 result = -EFAULT;
437 goto end;
438 }
439 memcpy(&pr->throttling.control_register, obj.buffer.pointer,
440 sizeof(struct acpi_ptc_register));
441
442 /*
443 * status_register
444 */
445
446 obj = ptc->package.elements[1];
447
448 if ((obj.type != ACPI_TYPE_BUFFER)
449 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
450 || (obj.buffer.pointer == NULL)) {
451 pr_err("Invalid _PTC data (status_register)\n");
452 result = -EFAULT;
453 goto end;
454 }
455
456 memcpy(&pr->throttling.status_register, obj.buffer.pointer,
457 sizeof(struct acpi_ptc_register));
458
459 throttling = &pr->throttling;
460
461 if ((throttling->control_register.bit_width +
462 throttling->control_register.bit_offset) > 32) {
463 pr_err("Invalid _PTC control register\n");
464 result = -EFAULT;
465 goto end;
466 }
467
468 if ((throttling->status_register.bit_width +
469 throttling->status_register.bit_offset) > 32) {
470 pr_err("Invalid _PTC status register\n");
471 result = -EFAULT;
472 goto end;
473 }
474
475end:
476 kfree(buffer.pointer);
477
478 return result;
479}
480
481/*
482 * _TSS - Throttling Supported States
483 */
484static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
485{
486 int result = 0;
487 acpi_status status = AE_OK;
488 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
489 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
490 struct acpi_buffer state = { 0, NULL };
491 union acpi_object *tss = NULL;
492 int i;
493
494 status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
495 if (ACPI_FAILURE(status)) {
496 if (status != AE_NOT_FOUND)
497 acpi_evaluation_failure_warn(pr->handle, "_TSS", status);
498
499 return -ENODEV;
500 }
501
502 tss = buffer.pointer;
503 if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) {
504 pr_err("Invalid _TSS data\n");
505 result = -EFAULT;
506 goto end;
507 }
508
509 acpi_handle_debug(pr->handle, "Found %d throttling states\n",
510 tss->package.count);
511
512 pr->throttling.state_count = tss->package.count;
513 pr->throttling.states_tss =
514 kmalloc_array(tss->package.count,
515 sizeof(struct acpi_processor_tx_tss),
516 GFP_KERNEL);
517 if (!pr->throttling.states_tss) {
518 result = -ENOMEM;
519 goto end;
520 }
521
522 for (i = 0; i < pr->throttling.state_count; i++) {
523
524 struct acpi_processor_tx_tss *tx =
525 (struct acpi_processor_tx_tss *)&(pr->throttling.
526 states_tss[i]);
527
528 state.length = sizeof(struct acpi_processor_tx_tss);
529 state.pointer = tx;
530
531 acpi_handle_debug(pr->handle, "Extracting state %d\n", i);
532
533 status = acpi_extract_package(&(tss->package.elements[i]),
534 &format, &state);
535 if (ACPI_FAILURE(status)) {
536 acpi_handle_warn(pr->handle, "Invalid _TSS data: %s\n",
537 acpi_format_exception(status));
538 result = -EFAULT;
539 kfree(pr->throttling.states_tss);
540 goto end;
541 }
542
543 if (!tx->freqpercentage) {
544 pr_err("Invalid _TSS data: freq is zero\n");
545 result = -EFAULT;
546 kfree(pr->throttling.states_tss);
547 goto end;
548 }
549 }
550
551end:
552 kfree(buffer.pointer);
553
554 return result;
555}
556
557/*
558 * _TSD - T-State Dependencies
559 */
560static int acpi_processor_get_tsd(struct acpi_processor *pr)
561{
562 int result = 0;
563 acpi_status status = AE_OK;
564 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
565 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
566 struct acpi_buffer state = { 0, NULL };
567 union acpi_object *tsd = NULL;
568 struct acpi_tsd_package *pdomain;
569 struct acpi_processor_throttling *pthrottling;
570
571 pthrottling = &pr->throttling;
572 pthrottling->tsd_valid_flag = 0;
573
574 status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
575 if (ACPI_FAILURE(status)) {
576 if (status != AE_NOT_FOUND)
577 acpi_evaluation_failure_warn(pr->handle, "_TSD", status);
578
579 return -ENODEV;
580 }
581
582 tsd = buffer.pointer;
583 if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) {
584 pr_err("Invalid _TSD data\n");
585 result = -EFAULT;
586 goto end;
587 }
588
589 if (tsd->package.count != 1) {
590 pr_err("Invalid _TSD data\n");
591 result = -EFAULT;
592 goto end;
593 }
594
595 pdomain = &(pr->throttling.domain_info);
596
597 state.length = sizeof(struct acpi_tsd_package);
598 state.pointer = pdomain;
599
600 status = acpi_extract_package(&(tsd->package.elements[0]),
601 &format, &state);
602 if (ACPI_FAILURE(status)) {
603 pr_err("Invalid _TSD data\n");
604 result = -EFAULT;
605 goto end;
606 }
607
608 if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) {
609 pr_err("Unknown _TSD:num_entries\n");
610 result = -EFAULT;
611 goto end;
612 }
613
614 if (pdomain->revision != ACPI_TSD_REV0_REVISION) {
615 pr_err("Unknown _TSD:revision\n");
616 result = -EFAULT;
617 goto end;
618 }
619
620 pthrottling = &pr->throttling;
621 pthrottling->tsd_valid_flag = 1;
622 pthrottling->shared_type = pdomain->coord_type;
623 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
624 /*
625 * If the coordination type is not defined in ACPI spec,
626 * the tsd_valid_flag will be clear and coordination type
627 * will be forecd as DOMAIN_COORD_TYPE_SW_ALL.
628 */
629 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
630 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
631 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
632 pthrottling->tsd_valid_flag = 0;
633 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
634 }
635
636end:
637 kfree(buffer.pointer);
638 return result;
639}
640
641/* --------------------------------------------------------------------------
642 Throttling Control
643 -------------------------------------------------------------------------- */
644static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr)
645{
646 int state = 0;
647 u32 value = 0;
648 u32 duty_mask = 0;
649 u32 duty_value = 0;
650
651 if (!pr)
652 return -EINVAL;
653
654 if (!pr->flags.throttling)
655 return -ENODEV;
656
657 /*
658 * We don't care about error returns - we just try to mark
659 * these reserved so that nobody else is confused into thinking
660 * that this region might be unused..
661 *
662 * (In particular, allocating the IO range for Cardbus)
663 */
664 request_region(pr->throttling.address, 6, "ACPI CPU throttle");
665
666 pr->throttling.state = 0;
667
668 duty_mask = pr->throttling.state_count - 1;
669
670 duty_mask <<= pr->throttling.duty_offset;
671
672 local_irq_disable();
673
674 value = inl(pr->throttling.address);
675
676 /*
677 * Compute the current throttling state when throttling is enabled
678 * (bit 4 is on).
679 */
680 if (value & 0x10) {
681 duty_value = value & duty_mask;
682 duty_value >>= pr->throttling.duty_offset;
683
684 if (duty_value)
685 state = pr->throttling.state_count - duty_value;
686 }
687
688 pr->throttling.state = state;
689
690 local_irq_enable();
691
692 acpi_handle_debug(pr->handle,
693 "Throttling state is T%d (%d%% throttling applied)\n",
694 state, pr->throttling.states[state].performance);
695
696 return 0;
697}
698
699#ifdef CONFIG_X86
700static int acpi_throttling_rdmsr(u64 *value)
701{
702 u64 msr_high, msr_low;
703 u64 msr = 0;
704 int ret = -1;
705
706 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
707 !this_cpu_has(X86_FEATURE_ACPI)) {
708 pr_err("HARDWARE addr space,NOT supported yet\n");
709 } else {
710 msr_low = 0;
711 msr_high = 0;
712 rdmsr_safe(MSR_IA32_THERM_CONTROL,
713 (u32 *)&msr_low, (u32 *) &msr_high);
714 msr = (msr_high << 32) | msr_low;
715 *value = (u64) msr;
716 ret = 0;
717 }
718 return ret;
719}
720
721static int acpi_throttling_wrmsr(u64 value)
722{
723 int ret = -1;
724 u64 msr;
725
726 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
727 !this_cpu_has(X86_FEATURE_ACPI)) {
728 pr_err("HARDWARE addr space,NOT supported yet\n");
729 } else {
730 msr = value;
731 wrmsr_safe(MSR_IA32_THERM_CONTROL,
732 msr & 0xffffffff, msr >> 32);
733 ret = 0;
734 }
735 return ret;
736}
737#else
738static int acpi_throttling_rdmsr(u64 *value)
739{
740 pr_err("HARDWARE addr space,NOT supported yet\n");
741 return -1;
742}
743
744static int acpi_throttling_wrmsr(u64 value)
745{
746 pr_err("HARDWARE addr space,NOT supported yet\n");
747 return -1;
748}
749#endif
750
751static int acpi_read_throttling_status(struct acpi_processor *pr,
752 u64 *value)
753{
754 u32 bit_width, bit_offset;
755 u32 ptc_value;
756 u64 ptc_mask;
757 struct acpi_processor_throttling *throttling;
758 int ret = -1;
759
760 throttling = &pr->throttling;
761 switch (throttling->status_register.space_id) {
762 case ACPI_ADR_SPACE_SYSTEM_IO:
763 bit_width = throttling->status_register.bit_width;
764 bit_offset = throttling->status_register.bit_offset;
765
766 acpi_os_read_port((acpi_io_address) throttling->status_register.
767 address, &ptc_value,
768 (u32) (bit_width + bit_offset));
769 ptc_mask = (1 << bit_width) - 1;
770 *value = (u64) ((ptc_value >> bit_offset) & ptc_mask);
771 ret = 0;
772 break;
773 case ACPI_ADR_SPACE_FIXED_HARDWARE:
774 ret = acpi_throttling_rdmsr(value);
775 break;
776 default:
777 pr_err("Unknown addr space %d\n",
778 (u32) (throttling->status_register.space_id));
779 }
780 return ret;
781}
782
783static int acpi_write_throttling_state(struct acpi_processor *pr,
784 u64 value)
785{
786 u32 bit_width, bit_offset;
787 u64 ptc_value;
788 u64 ptc_mask;
789 struct acpi_processor_throttling *throttling;
790 int ret = -1;
791
792 throttling = &pr->throttling;
793 switch (throttling->control_register.space_id) {
794 case ACPI_ADR_SPACE_SYSTEM_IO:
795 bit_width = throttling->control_register.bit_width;
796 bit_offset = throttling->control_register.bit_offset;
797 ptc_mask = (1 << bit_width) - 1;
798 ptc_value = value & ptc_mask;
799
800 acpi_os_write_port((acpi_io_address) throttling->
801 control_register.address,
802 (u32) (ptc_value << bit_offset),
803 (u32) (bit_width + bit_offset));
804 ret = 0;
805 break;
806 case ACPI_ADR_SPACE_FIXED_HARDWARE:
807 ret = acpi_throttling_wrmsr(value);
808 break;
809 default:
810 pr_err("Unknown addr space %d\n",
811 (u32) (throttling->control_register.space_id));
812 }
813 return ret;
814}
815
816static int acpi_get_throttling_state(struct acpi_processor *pr,
817 u64 value)
818{
819 int i;
820
821 for (i = 0; i < pr->throttling.state_count; i++) {
822 struct acpi_processor_tx_tss *tx =
823 (struct acpi_processor_tx_tss *)&(pr->throttling.
824 states_tss[i]);
825 if (tx->control == value)
826 return i;
827 }
828 return -1;
829}
830
831static int acpi_get_throttling_value(struct acpi_processor *pr,
832 int state, u64 *value)
833{
834 int ret = -1;
835
836 if (state >= 0 && state <= pr->throttling.state_count) {
837 struct acpi_processor_tx_tss *tx =
838 (struct acpi_processor_tx_tss *)&(pr->throttling.
839 states_tss[state]);
840 *value = tx->control;
841 ret = 0;
842 }
843 return ret;
844}
845
846static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
847{
848 int state = 0;
849 int ret;
850 u64 value;
851
852 if (!pr)
853 return -EINVAL;
854
855 if (!pr->flags.throttling)
856 return -ENODEV;
857
858 pr->throttling.state = 0;
859
860 value = 0;
861 ret = acpi_read_throttling_status(pr, &value);
862 if (ret >= 0) {
863 state = acpi_get_throttling_state(pr, value);
864 if (state == -1) {
865 acpi_handle_debug(pr->handle,
866 "Invalid throttling state, reset\n");
867 state = 0;
868 ret = __acpi_processor_set_throttling(pr, state, true,
869 true);
870 if (ret)
871 return ret;
872 }
873 pr->throttling.state = state;
874 }
875
876 return 0;
877}
878
879static long __acpi_processor_get_throttling(void *data)
880{
881 struct acpi_processor *pr = data;
882
883 return pr->throttling.acpi_processor_get_throttling(pr);
884}
885
886static int acpi_processor_get_throttling(struct acpi_processor *pr)
887{
888 if (!pr)
889 return -EINVAL;
890
891 if (!pr->flags.throttling)
892 return -ENODEV;
893
894 /*
895 * This is either called from the CPU hotplug callback of
896 * processor_driver or via the ACPI probe function. In the latter
897 * case the CPU is not guaranteed to be online. Both call sites are
898 * protected against CPU hotplug.
899 */
900 if (!cpu_online(pr->id))
901 return -ENODEV;
902
903 return call_on_cpu(pr->id, __acpi_processor_get_throttling, pr, false);
904}
905
906static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
907{
908 int i, step;
909
910 if (!pr->throttling.address) {
911 acpi_handle_debug(pr->handle, "No throttling register\n");
912 return -EINVAL;
913 } else if (!pr->throttling.duty_width) {
914 acpi_handle_debug(pr->handle, "No throttling states\n");
915 return -EINVAL;
916 }
917 /* TBD: Support duty_cycle values that span bit 4. */
918 else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
919 pr_warn("duty_cycle spans bit 4\n");
920 return -EINVAL;
921 }
922
923 pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
924
925 /*
926 * Compute state values. Note that throttling displays a linear power
927 * performance relationship (at 50% performance the CPU will consume
928 * 50% power). Values are in 1/10th of a percent to preserve accuracy.
929 */
930
931 step = (1000 / pr->throttling.state_count);
932
933 for (i = 0; i < pr->throttling.state_count; i++) {
934 pr->throttling.states[i].performance = 1000 - step * i;
935 pr->throttling.states[i].power = 1000 - step * i;
936 }
937 return 0;
938}
939
940static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
941 int state, bool force)
942{
943 u32 value = 0;
944 u32 duty_mask = 0;
945 u32 duty_value = 0;
946
947 if (!pr)
948 return -EINVAL;
949
950 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
951 return -EINVAL;
952
953 if (!pr->flags.throttling)
954 return -ENODEV;
955
956 if (!force && (state == pr->throttling.state))
957 return 0;
958
959 if (state < pr->throttling_platform_limit)
960 return -EPERM;
961 /*
962 * Calculate the duty_value and duty_mask.
963 */
964 if (state) {
965 duty_value = pr->throttling.state_count - state;
966
967 duty_value <<= pr->throttling.duty_offset;
968
969 /* Used to clear all duty_value bits */
970 duty_mask = pr->throttling.state_count - 1;
971
972 duty_mask <<= acpi_gbl_FADT.duty_offset;
973 duty_mask = ~duty_mask;
974 }
975
976 local_irq_disable();
977
978 /*
979 * Disable throttling by writing a 0 to bit 4. Note that we must
980 * turn it off before you can change the duty_value.
981 */
982 value = inl(pr->throttling.address);
983 if (value & 0x10) {
984 value &= 0xFFFFFFEF;
985 outl(value, pr->throttling.address);
986 }
987
988 /*
989 * Write the new duty_value and then enable throttling. Note
990 * that a state value of 0 leaves throttling disabled.
991 */
992 if (state) {
993 value &= duty_mask;
994 value |= duty_value;
995 outl(value, pr->throttling.address);
996
997 value |= 0x00000010;
998 outl(value, pr->throttling.address);
999 }
1000
1001 pr->throttling.state = state;
1002
1003 local_irq_enable();
1004
1005 acpi_handle_debug(pr->handle,
1006 "Throttling state set to T%d (%d%%)\n", state,
1007 (pr->throttling.states[state].performance ? pr->
1008 throttling.states[state].performance / 10 : 0));
1009
1010 return 0;
1011}
1012
1013static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
1014 int state, bool force)
1015{
1016 int ret;
1017 u64 value;
1018
1019 if (!pr)
1020 return -EINVAL;
1021
1022 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1023 return -EINVAL;
1024
1025 if (!pr->flags.throttling)
1026 return -ENODEV;
1027
1028 if (!force && (state == pr->throttling.state))
1029 return 0;
1030
1031 if (state < pr->throttling_platform_limit)
1032 return -EPERM;
1033
1034 value = 0;
1035 ret = acpi_get_throttling_value(pr, state, &value);
1036 if (ret >= 0) {
1037 acpi_write_throttling_state(pr, value);
1038 pr->throttling.state = state;
1039 }
1040
1041 return 0;
1042}
1043
1044static long acpi_processor_throttling_fn(void *data)
1045{
1046 struct acpi_processor_throttling_arg *arg = data;
1047 struct acpi_processor *pr = arg->pr;
1048
1049 return pr->throttling.acpi_processor_set_throttling(pr,
1050 arg->target_state, arg->force);
1051}
1052
1053static int __acpi_processor_set_throttling(struct acpi_processor *pr,
1054 int state, bool force, bool direct)
1055{
1056 int ret = 0;
1057 unsigned int i;
1058 struct acpi_processor *match_pr;
1059 struct acpi_processor_throttling *p_throttling;
1060 struct acpi_processor_throttling_arg arg;
1061 struct throttling_tstate t_state;
1062
1063 if (!pr)
1064 return -EINVAL;
1065
1066 if (!pr->flags.throttling)
1067 return -ENODEV;
1068
1069 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1070 return -EINVAL;
1071
1072 if (cpu_is_offline(pr->id)) {
1073 /*
1074 * the cpu pointed by pr->id is offline. Unnecessary to change
1075 * the throttling state any more.
1076 */
1077 return -ENODEV;
1078 }
1079
1080 t_state.target_state = state;
1081 p_throttling = &(pr->throttling);
1082
1083 /*
1084 * The throttling notifier will be called for every
1085 * affected cpu in order to get one proper T-state.
1086 * The notifier event is THROTTLING_PRECHANGE.
1087 */
1088 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
1089 t_state.cpu = i;
1090 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
1091 &t_state);
1092 }
1093 /*
1094 * The function of acpi_processor_set_throttling will be called
1095 * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1096 * it is necessary to call it for every affected cpu. Otherwise
1097 * it can be called only for the cpu pointed by pr.
1098 */
1099 if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
1100 arg.pr = pr;
1101 arg.target_state = state;
1102 arg.force = force;
1103 ret = call_on_cpu(pr->id, acpi_processor_throttling_fn, &arg,
1104 direct);
1105 } else {
1106 /*
1107 * When the T-state coordination is SW_ALL or HW_ALL,
1108 * it is necessary to set T-state for every affected
1109 * cpus.
1110 */
1111 for_each_cpu_and(i, cpu_online_mask,
1112 p_throttling->shared_cpu_map) {
1113 match_pr = per_cpu(processors, i);
1114 /*
1115 * If the pointer is invalid, we will report the
1116 * error message and continue.
1117 */
1118 if (!match_pr) {
1119 acpi_handle_debug(pr->handle,
1120 "Invalid Pointer for CPU %d\n", i);
1121 continue;
1122 }
1123 /*
1124 * If the throttling control is unsupported on CPU i,
1125 * we will report the error message and continue.
1126 */
1127 if (!match_pr->flags.throttling) {
1128 acpi_handle_debug(pr->handle,
1129 "Throttling Control unsupported on CPU %d\n", i);
1130 continue;
1131 }
1132
1133 arg.pr = match_pr;
1134 arg.target_state = state;
1135 arg.force = force;
1136 ret = call_on_cpu(pr->id, acpi_processor_throttling_fn,
1137 &arg, direct);
1138 }
1139 }
1140 /*
1141 * After the set_throttling is called, the
1142 * throttling notifier is called for every
1143 * affected cpu to update the T-states.
1144 * The notifier event is THROTTLING_POSTCHANGE
1145 */
1146 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
1147 t_state.cpu = i;
1148 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1149 &t_state);
1150 }
1151
1152 return ret;
1153}
1154
1155int acpi_processor_set_throttling(struct acpi_processor *pr, int state,
1156 bool force)
1157{
1158 return __acpi_processor_set_throttling(pr, state, force, false);
1159}
1160
1161int acpi_processor_get_throttling_info(struct acpi_processor *pr)
1162{
1163 int result = 0;
1164 struct acpi_processor_throttling *pthrottling;
1165
1166 acpi_handle_debug(pr->handle,
1167 "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1168 pr->throttling.address,
1169 pr->throttling.duty_offset,
1170 pr->throttling.duty_width);
1171
1172 /*
1173 * Evaluate _PTC, _TSS and _TPC
1174 * They must all be present or none of them can be used.
1175 */
1176 if (acpi_processor_get_throttling_control(pr) ||
1177 acpi_processor_get_throttling_states(pr) ||
1178 acpi_processor_get_platform_limit(pr)) {
1179 pr->throttling.acpi_processor_get_throttling =
1180 &acpi_processor_get_throttling_fadt;
1181 pr->throttling.acpi_processor_set_throttling =
1182 &acpi_processor_set_throttling_fadt;
1183 if (acpi_processor_get_fadt_info(pr))
1184 return 0;
1185 } else {
1186 pr->throttling.acpi_processor_get_throttling =
1187 &acpi_processor_get_throttling_ptc;
1188 pr->throttling.acpi_processor_set_throttling =
1189 &acpi_processor_set_throttling_ptc;
1190 }
1191
1192 /*
1193 * If TSD package for one CPU can't be parsed successfully, it means
1194 * that this CPU will have no coordination with other CPUs.
1195 */
1196 if (acpi_processor_get_tsd(pr)) {
1197 pthrottling = &pr->throttling;
1198 pthrottling->tsd_valid_flag = 0;
1199 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
1200 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
1201 }
1202
1203 /*
1204 * PIIX4 Errata: We don't support throttling on the original PIIX4.
1205 * This shouldn't be an issue as few (if any) mobile systems ever
1206 * used this part.
1207 */
1208 if (errata.piix4.throttle) {
1209 acpi_handle_debug(pr->handle,
1210 "Throttling not supported on PIIX4 A- or B-step\n");
1211 return 0;
1212 }
1213
1214 acpi_handle_debug(pr->handle, "Found %d throttling states\n",
1215 pr->throttling.state_count);
1216
1217 pr->flags.throttling = 1;
1218
1219 /*
1220 * Disable throttling (if enabled). We'll let subsequent policy (e.g.
1221 * thermal) decide to lower performance if it so chooses, but for now
1222 * we'll crank up the speed.
1223 */
1224
1225 result = acpi_processor_get_throttling(pr);
1226 if (result)
1227 goto end;
1228
1229 if (pr->throttling.state) {
1230 acpi_handle_debug(pr->handle,
1231 "Disabling throttling (was T%d)\n",
1232 pr->throttling.state);
1233 result = acpi_processor_set_throttling(pr, 0, false);
1234 if (result)
1235 goto end;
1236 }
1237
1238end:
1239 if (result)
1240 pr->flags.throttling = 0;
1241
1242 return result;
1243}
1244